GRAPE
Grapes are the fruit of a vine (Vitis vinifera). The whole fruit, skin, leaves and seed of the grape plant are used as medicine. Grape seeds are by-products of the manufacturing of wine. Be careful not to confuse grape with grapefruit, and other similar sounding medicines.
Grape is used for preventing diseases of the heart and blood vessels, varicose veins, hemorrhoids, “hardening of the arteries” (atherosclerosis), high blood pressure, swelling after injury or surgery, heart attack, and stroke.
Some people also use grape as a mild laxative for constipation. You have probably heard of grape “fasts” as part of “detoxification.”
Grape seed is used for diabetes complications such as nerve and eye problems, improving wound healing, preventing tooth decay, preventing cancer, an eye disease called age-related macular degeneration (AMD), poor night vision, liver disorders, and hay fever.
Dried grapes, raisins, or sultanas (white raisins) are used for cough.
Grape leaf is used for attention deficit-hyperactivity disorder (ADHD), chronic fatigue syndrome (CFS), diarrhea, heavy menstrual bleeding, uterine bleeding, and canker sores.
Grape leaf is used as a food, particularly in Greek cooking.
How does it work?
Grape contains flavonoids, which can have antioxidant effects, lower the levels of low density lipoproteins (LDLs, or “bad cholesterol”), relax blood vessels, and reduce the risk of coronary heart disease. The antioxidants in grape might help to prevent heart disease and have other potentially beneficial effects. Red grape varieties provide more antioxidants than white or blush grape varieties.
Grape leaf might reduce inflammation and have astringent effects. In other words, grape leaf seems to be able to draw tissue together, which could help stop bleeding and diarrhea. These properties appear to be greatest in the red leaves.
Grape is POSSIBLY SAFE when taken by mouth in medicinal amounts. Grape seed extracts have been used safely in studies for up to 14 weeks. Eating large quantities of grapes, dried grapes, raisins, or sultanas might cause diarrhea. Some people have allergic reactions to grapes and grape products. Some other potential side effects include stomach upset, indigestion, nausea, vomiting, cough, dry mouth, sore throat, infections, headache, and muscular problems.
Special Precautions & Warnings:
Pregnancy and breast-feeding: Not enough is known about the use of grape in medicinal amounts (supplements or amounts that are higher than normal food amounts) during pregnancy and breast-feeding. Stay on the safe side and avoid use.
Bleeding conditions: Grape might slow blood clotting. Taking grape might increase the chances of bruising and bleeding in people with bleeding conditions. However, there are no reports of this occurring in humans.
Surgery: Grape might slow blood clotting. It might cause extra bleeding during and after surgery. Stop using medicinal amounts of grape at least 2 weeks before a scheduled surgery.
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Food as Medicine: Grapes
(Vitis vinifera, Vitaceae)
History and Traditional Use
Range and Habitat
Vitis vinifera means “the vine that bears wine” and belongs to the Vitaceae family. Grapes are perennial climbers that have coiled tendrils and large leaves. They contain clusters of flowers that mature to produce small, round, and juicy berries that can be either green (“white”) or red.1 There are seed and seedless varieties, although the seeds are edible and packed with nutrition. The juice, pulp, skin, and seed of the grape can be used for various preparations.2
Grapes are a vine and must be trained to grow along a fence, wall, or arbor.3 The fruit does not ripen after harvesting; therefore, it is important to harvest well-colored and plump berries that are wrinkle-free and still firmly attached to the vine. They are best stored in the refrigerator since freezing will decrease their flavor.1,4 Pesticide use is common in vineyards, and careful washing is recommended when purchasing conventionally grown grapes.
As one of the leading commercial fruit crops in the world in terms of tons produced, grapes are cultivated all over the world in temperate regions. The top producers are Italy, France, Spain, the United States, Mexico, and Chile.1,5 Annually, worldwide grape production reaches an average of 60 million metric tons, 5.2 million of which are grown in the United States.
Phytochemicals and Constituents
Antioxidants are enzymes and nutrients that prevent oxidation, meaning they neutralize highly reactive ions or molecules known as free radicals in the human body by donating electrons, or modulating enzymes that metabolize free radicals. Free radicals are produced naturally through metabolism as part of normal physiological functions (e.g., a defense mechanism against pathogens), but may be produced in excess, creating a situation where they adversely alter lipids, proteins, and DNA, and trigger a number of human diseases. Grape and grape products are good sources of beneficial antioxidant compounds.
Grapes contain phytochemicals called polyphenols. Polyphenols are the most abundant source of dietary antioxidants and are associated with numerous health benefits.2,6 The phenolic compounds are more concentrated in the skin of the berry, rather than in the flesh or seeds, and the content tends to increase as the fruit ripens. Grapes contain polyphenols from the classes of flavonoids, stilbenes, and phenolic acids. Red wine and grapes are rich in flavonoids such as anthocyanins and catechins, stilbenes such as resveratrol, and phenolic acids such as caffeic acid and coumaric acid. Red grapes have higher concentrations of these phenolic compounds than red wine grapes. Different grape varietals contain varying amounts of phenolic compounds.
Anthocyanins are flavonoids that naturally occur in the plant kingdom and give many plants their red, purple, or blue pigmentation. Vitis vinifera may contain up to 17 anthocyanin pigments, which are contained in the skins.2,7 Grapes also contain other flavonoids, including catechins, epicatechins, and proanthocyanidins. Attempts to study the benefits of individual phytochemicals in humans has been difficult since these phytochemicals are complex and often interact with one another to increase their overall benefits.
There are numerous studies using animal models in phytochemical research.8 Animal models have shown that anthocyanins protect against oxidative stress, which can be the beginning stages of many chronic conditions, such as cardiovascular disease, diabetes, and cancer.
Grape seeds are a particularly rich source of proanthocyanidins, a class of nutrients belonging to the flavonoid family. Proanthocyanidins, also known as condensed tannins, are polymers (naturally occurring large molecules) with flavan-3-ol monomers as building blocks. The term oligomeric proanthocyanidin (OPC), which also is commonly used to describe these compounds, is not well-defined and is debated among various members of the scientific community.
Grape seed extract is available as a nutritional supplement. Partially purified proanthocyanidins have been used in phytomedicinal preparations in Europe for their purported activity in decreasing the fragility and permeability of the blood vessels outside the heart and brain.9
Grapes have a high stilbene, specifically resveratrol, content. Resveratrol, which is found in the skin and seeds of red grapes as well as in red wine, is produced as the plant’s defense mechanism against environmental stressors.1,2,10,11 Resveratrol first gained attention as a possible explanation for the “French Paradox” — the observation that French people tend to have a low incidence of heart disease despite having a typically high-fat diet.1 The antioxidant activity of grapes is strongly correlated with the amount of resveratrol found in the grape.10 Studies have found resveratrol to be anti-carcinogenic, anti-inflammatory, and cardio-protective in animal models.11 However, in a human study in which healthy adults consumed resveratrol, it was determined that the compound was readily absorbed, but it metabolized quickly, leaving only trace amounts.12
In addition to their high resveratrol content, grapes are also an excellent source of vitamin K and provide moderate amounts of potassium, vitamin C, and B vitamins.
Historical and Commercial Uses
Grapes have been consumed since prehistoric times and were one of the earliest domesticated fruit crops.1,13 According to ancient Mediterranean culture, the “vine sprang from the blood of humans who had fought against the gods.”14 But according to archaeological evidence, domestication took place about 5,000 years ago somewhere between the Caspian and Black Seas, and spread south to modern-day Syria, Iraq, Jordan, and Egypt before moving towards Europe.5,13 After the collapse of the Roman Empire in the 5th century, when Christianity became dominant, wine was associated with the Church and the monasteries soon perfected the process of making wine.1
About 300 years ago, Spanish explorers introduced the grape to what is now the United States, and California’s temperate climate proved to be an ideal place for grape cultivation.1
The grape is, famously, the most common ingredient in wine-making. A naturally-occurring symbiotic yeast grows on the grapes, making them easier to ferment and well-suited to the wine-making process.4 Popular wine cultivars of V. vinifera include Cabernet Sauvignon, Merlot, Chardonnay, Sauvignon Blanc, Vermentino, and Viognier.10
Wine often has been used as a medium for herbal remedies, due to the solvent nature of the alcohol. Both the Chinese and Western traditions made use of medicated wines (though ancient recipes in China, which date to the Shang Dynasty [ca 1600-1046 BCE], would have been made with rice [Oryza sativa, Poaceae] wine rather than grape wine).15 Many aperitifs and liqueurs originally were digestive aids made with wine and fortified with herbs such as wormwood (Artemisia absinthium, Asteraceae) and anise seed (Pimpinella anisum, Apiaceae).16 Medicated wines are less potent and usually require a higher dosage than tinctures made with higher-proof alcohol.
Grapes are generally sweet and are used as table grapes, juice, jam, jelly, or for wine-making.13,17 About 99% of the world’s wine comes from V. vinifera.14 Grapes can also be dried in the vineyard and turned into raisins. To accomplish this, ripe grapes are plucked from the vine and placed on paper trays for two to four weeks. Afterwards, they are sent to the processing plant to be cleaned, packaged, and shipped.5
Modern Research
Grapes have been the subject of numerous studies focused on many of their bioactive compounds, including flavonoids, stilbenes, and phenolic acids. Researchers have observed antioxidant, anti-tumor, immune modulatory, anti-diabetic, anti-atherogenic, anti-infectious, and neuro-protective properties of the fruit.11 Research suggests that grape product consumption could possibly benefit those with cancer, diabetes, and cardiovascular disease, which are among the leading causes of death worldwide.18 However, more human studies are needed to support any of these purported benefits.
An in vitro study showed that antioxidants from a variety of grape product extracts performed as well as or better than BHT, tocopherol, and trolox in radical scavenging activity, metal chelating activity, and inhibition of lipid peroxidation.7 Water and ethanol seed extracts had the highest amount of phenolic compounds of any of the extracts used in the study.
Grape seed extract (GSE), which has a growing body of study behind it, has gained attention for its possible use in lowering blood pressure and reducing the risk of heart disease, especially in pre-hypertensive populations.19 Unlike grape skins, where only red grapes contain anthocyanins, seeds from both white and red grape contain beneficial compounds. A standardized GSE made from white wine grapes recently was studied for its effects on gastrointestinal inflammation.20 While most studies focus on GSE and cardiovascular health, the preliminary results were promising enough to warrant a future human trial.
Cardiovascular Disease
Polyphenols have been found to protect the body from inflammation, which is common in people with heart disease.11 In a recent meta-analysis, the acute effects of polyphenols on the endothelium (inner lining of the blood vessels) were investigated. The analysis found that blood vessel function significantly improved in healthy adults in the initial two hours after consuming grape polyphenols.21 Another analysis found that the polyphenol content in every part of the grape — fruit, skin, and seed — had cardioprotective effects.22 In animal, in vitro, and limited human trials, grapes showed beneficial actions against oxidative stress, atherosclerosis (plaque build-up in arteries), high blood pressure, and ventricular arrhythmia (irregular heartbeat).
Cancer Chemopreventive Effects
Although the causes of and treatments for cancer are complex and multifaceted, studies have been done on the antioxidant activity of polyphenols and their cancer chemopreventive effects. These antioxidants demonstrate the ability to protect the body from cancer-causing substances and to prevent tumor cell growth by protecting DNA and regulating natural cell death.8,11,23
Diabetes
In a randomized, double-blind controlled clinical study, healthy overweight/obese first degree relatives to type 2 diabetic patients were given grape polyphenols to counteract a high-fructose diet. After nine weeks of supplementation, grape polyphenols protected against fructose-induced insulin resistance.24 In another study, diabetic patients who consumed a dealcoholized Muscadine grape wine had reduced fasting insulin levels and increased insulin resistance.25
Nutrient Profile26
Macronutrient Profile: (Per 150 g [approx. 1 cup] grapes)
104 calories
1.1 g protein
27.3 g carbohydrate
0.2 g fat
Secondary Metabolites: (Per 150 g [approx. 1 cup] grapes)
Excellent source of:
Vitamin K: 22 mcg (27.5% DV)
Good source of:
Potassium: 288 mg (8.2% DV)
Vitamin C: 4.8 mg (8% DV)
Thiamin: 0.1 mg (6.7% DV)
Riboflavin: 0.1 mg (5.9% DV)
Dietary Fiber: 1.4 g (5.6% DV)
Manganese: 0.1 mg (5.5% DV)
Vitamin B6: 0.1 mg (5% DV)
Also provides:
Phosphorus: 30 mg (3% DV)
Magnesium: 11 mg (2.8% DV)
Iron: 0.5 mg (2.8% DV)
Vitamin A: 100 IU (2% DV)
Niacin: 0.3 mg (1.5% DV)
Vitamin E: 0.3 mg (1.5% DV)
DV = Daily Value as established by the US Food and Drug Administration, based on a 2,000 calorie diet.
—Hannah Bauman
References
1. Murray MT, Pizzorno J, Pizzorno L. The Encyclopedia of Healing Foods. New York, NY: Atria Books; 2005.
2. Yang J, Xiao YY. Grape phytochemcials and associated health benefits. Critical Reviews in Food Science and Nutrition. 2013;53:1202-1225.
3. Damrosch B. Grapes. In: The Garden Primer: Second Edition. New York, NY: Workman Publishing; 2008:353-359.
4. Wood R. The New Whole Foods Encyclopedia: A Comprehensive Resource for Healthy Eating. New York, NY: Penguin Books; 1999.
5. Ensminger AH, Ensminger ME, Konlande JE. The Concise Encyclopedia of Foods & Nutrition. Boca Raton, FL: CRC Press; 1995.
6. Tiwari B, Brunton NP, Brennan CS. Handbook of Plant Food Phytochemicals. London, UK: John Wiley & Sons, Ltd; 2013.
7. Keser S, Celik S, and Turkoglu S. Total phenolic contents and free-radical scavenging activities of grape (Vitis vinifera L.) and grape products. International Journal of Food Sciences and Nutrition. 2013;64(2):210-216.
8. Lila MA. Anthocyanins and human health: An in vitro investigative approach. J Biomed Biotechnol. 2004;2004(5):306-313.
9. Yamakoshi J, Saito M, Kataoka S, Kikuchi M. Safety evaluation of proanthocyanidin-rich extract from grape seeds. Food and Chemical Toxicology. 2002;40:599-607.
10. Burin VM, Ferreira-Lima NE, Panceri CP, Bordignon-Luiz MT. Bioactive compounds and antioxidant activity of Vitis vinifera and Vitis labrusca grapes: Evaluation of different extraction methods. Microchemical Journal. 2014;114:155-163.
11. Yadav M, Jain S, Bhardwaj A, et al. Biological and medicinal properties of grapes and their bioactive constituents: An update. Journal of Medinical Food. 2009;12(3):473-484.
12. Walle T, Hsieh F, DeLegge MH, Oatis JE, Walle K. High absorption but very low bioavailability of oral resveratrol in humans. Drug Metabolism and Disposition. 2004;32(12):1377-1382.
13. Myles S, Boyko AR, Owens CL, et al. Genetic structure and domestication history of the grape. Proceedings of the National Academy of Science of the United States of America. 2011;108(9):3530-3535.
14. McGovern PE. Ancient Wine: The Search for the Origins of Viniculture. Princeton, NJ: Princeton University Press; 2007.
15. Chan K, Cheung L. Interactions Between Chinese Herbal Medicinal Products and Orthodox Drugs. Boca Raton, FL: CRC Press; 2000.
16. Hoffmann D. The Herbal Handbook: A User’s Guide to Medical Herbalism. Rochester, VT: Inner Traditions; 1998.
17. Onstad D. Whole Foods Companion: A Guide for Adventurous Cooks, Curious Shoppers, and Lovers of Natural Foods. White River Junction, VT: Chelsea Green Publishing; 2004.
18. The top 10 causes of death – fact sheet no. 310. World Health Organization website. May 2014. Available here. Accessed November 23, 2015.
19. Park E, Edirisinghe I, Choy YY, Waterhouse A, Burton-Freeman B. Effects of grape seed extract beverage on blood pressure and metabolic indices in individuals with pre-hypertension: a randomised, double-blinded, two-arm, parallel, placebo-controlled trial. Br J Nutr. 2015;16:1-13.
20. Starling S. White wine extract shows gastro benefits in vitro. Clinicals planned for 2016. NutraIngredients-USA website. November 12, 2015. Available here. Accessed November 19, 2015.
21. Li SH, Tian HB, Zhao HJ, Chen LH, Cui LQ. The acute effects of grape polyphenols supplementation on endothelial function in adults. PLOS ONE. 2013;8(7):e69818.
22. Leifert WR, Abeywardena MY. Cardioprotective actions of grape polyphenols. Nutrition Research. 2008;28:729-737.
23. Waffo-Téguo P, Hawthorne ME, Cuendet M, et al. Potential cancer-chemopreventive activities of wine stilbenoids and flavans extracted from grape (Vitis vinifera) cell cultures. Nutrition and Cancer. 2001;40(2):173-179.
24. Hokayem M. Grape polyphenols prevent fructose-induced oxidative stress and insulin resistance in first-degree relatives of type 2 diabetic patients. Diabetes Care. 2013;36:1455-1461.
25. Banini AE, Boyd LG, Allen JG, Allen HG, Sauls DL. Muscadine grape products intake, diet and blood constituents of non-diabetic and type 2 diabetic subjects. Nutrition. 2006;22:1137-45.
26. Basic Report: 09132, Grapes, red or green (European type, such as Thompson seedless), raw. United States Department of Agriculture, Agricultural
LEXIKON DER ARZNEIPFLANZEN UND DROGEN; Vitis vinifera L. ssp. vinifera
Wein (syn. Weinstock, Weinrebe).
Fam.: Vitaceae.
Vork.: Mittel- und Südeuropa, Vorderasien, Mittel- und Südamerika, Australien, Neuseeland, in der Regel kultiviert.
Droge:
1. Vitis viniferae folium (syn. Folia Vitis viniferae); Weinrebenblätter (syn. Weinblätter), die frischen Laubblätter. Inh.: Tartrate, u.a. Kaliumbitartrat (ca. 2 %), und Calciumbitartrat, ferner Calciumoxalat, freie Wein-, Äpfel- und Bernsteinsäure, Zucker (ca. 2 %), Flavonoide, wie Quercitrin und Quercetin, sowie Gerbstoffe. Anw.: in der Volksheilkunde bei Hautleiden, Blutungen und Dysenterie. Aus den Weinranken (Pampini Vitis) wurde früher Extractum Vitis pampinorum für diese Indikationen hergestellt.
2. Oleum Vitis viniverae e seminibus; Traubenkernöl, das fette Öl der Kerne. Inh.: Triglyceride, die Palmitinsäure (8-10 %), Stearinsäure (3-5 %), Ölsäure (10-20 %), Linolsäure (65-70 %) sowie Myristin- und Linolensäure als Fettsäurekomponenten enthalten. Anw.: als Diätetikum, Speise- und Backöl; in der Farbenindustrie zur Gewinnung von Firnissen, in der Linoleum- und Seifenherstellung.
3. Fructus Vitis; Weinbeeren (syn. Weintrauben), die reifen Früchte. Inh.: Weinsäure (0,3-0,4 %), Äpfelsäure (0,3-0,4 %), Tartrate (0,4-0,6 %), Zucker (3-15 %), Pektine (ca. 3 %), Pentosane, Gerbstoffe, Quercitrin und Quercetin, in blauen Trauben Oenin, Anthocyane, Xanthophylle, Cartozine, Vitamine A, B1, B2, C, Gerbstoffe, Vanillin, fettes Öl. Anw.: zur "Traubenkur", d.h. durch die laxierenden und diuretischen Effekte der Tartrate bei Stoffwechselkrankheiten, Verstopfung, Hauterkrankungen, Fettsucht, Herzleiden; zur Herstellung von Traubensaft bzw. zur Weinherstellung (s. Vinum).
4. Passulae majores (syn. Uvae passae); Rosinen (syn. Sultanas, Sultaninen, Zibeben), die getrockneten Früchte. Inh.: Fruchtsäuren (ca. 1,5 %), Dextrose (ca. 28 %), Lävulose (ca. 34 %), Mineralien. Anw.: in der Backwarenindustrie, für Suppen, Süßspeisen, Puddings, Schokoladenprodukte etc.Die besten Produkte stammen aus Spanien, Frankreich, Griechenland, Kleinasien und Kalifornien.
5. Passulae minores (syn. Uvae corinthiacae); Korinthen, die getrockneten Früchte von Vitis vinifera var. apyrena, dessen Anbaugebiete Griechenland (Korinth) und Australien sind. Inh.: Fruchtsäuren (2,5 %), Zucker (ca. 53 %), Proteine (ca. 2,8 %). Anw.: für Backwaren, Puddings und Suppen. 6. Vinum; Wein, das durch alkoholische Gärung aus dem Saft der frischen Weintraube hergestellte Getränk. Für arzneiliche Zwecke werden hauptsächlich süße Weine, wie Xereswein (Cherry) oder Vinum dulce (Süßwein) eingesetzt. Inh.: Ethanol (je nach Traubensorte, Erntezeitpunkt und Anbaugebiet zwischen 6 und maximal 16 %), Zucker, Tartrate, Fruchtsäuren, Duftstoffe, Farbstoffe, Gerbstoffe, Mineralien, Alkaloide (Salsolin), Amine (Serotonin, Dopamin), Resveratrol. Anw.: hauptsächlich als Genußmittel, zur Bereitung der Arzneiweine (Vinum medicatum), früher auch als Stärkungsmittel. Bei mäßigem Weingenuß wird eine protektive Wirkung bezüglich der Arteriosklerose und koronaren Herzerkrankungen beobachtet.
Hom.: Vitis vinifera HAB 34; Wein, die frischen Blätter.
Food Funct. 2013 Feb 26;4(3):366-72. doi: 10.1039/c2fo30259d.bChemopreventive properties of raisins originating from Greece in colon cancer cells.
Kountouri AM1, Gioxari A, Karvela E, Kaliora AC, Karvelas M, Karathanos VT.
Colorectal cancer is one of the major causes of cancer-related mortality in humans in both developed and developing countries. Dietary patterns influence the risk of colon cancer development, while plant-derived foods have gained great interest, due to the high content of antioxidants. Corinthian raisins (Currants, CR) and Sultanas (S) (Vitis vinifera L., Vitaceae) are dried vine fruits produced in Greece with many culinary uses in both the Mediterranean and the Western nutrition. In the present study, we investigated the effects of CR and S on human colon cancer cells. Methanol extracts of CR and S were used at different concentrations. The total polyphenol content and anti-radical activity were measured by Folin-Ciocalteu and DPPH, respectively. Antioxidant, anti-inflammatory and anti-proliferative effects on HT29 cell culture were evaluated. All extracts exhibited DPPH˙ scavenging activity in a dose-dependent manner. Both products suppressed cell proliferation, while the levels of glutathione and cyclooxygenase 2 were significantly decreased. A significant reduction in IL-8 levels and NF-kappaB p65 activation was also observed. Both antioxidant and anti-inflammatory effects were dependent on the duration of exposure. Results indicate that the methanol extracts of CR and S exhibit anti-radical activity in vitro, as well as cancer preventive efficacy on colon cancer cells, with S having slightly higher activity. The beneficial properties of these unique dried grapes are attributed to their high content of phenolic compounds.
Nutr Res. 2010 Aug;30(8):511-9. doi: 10.1016/j.nutres.2010.07.005.Polyphenol content and health benefits of raisins.
Williamson G1, Carughi A.
The health benefits of grapes and wine have been studied and publicized extensively, but dried grapes (raisins, including "sultanas" and "currants") have received comparatively little attention. The purpose of the review was to summarize the polyphenol, phenolic acid, and tannin (PPT) composition of raisins; predict the likely bioavailability of the component PPT; and summarize the results of human intervention studies involving raisins. The most abundant PPTs are the flavonols, quercetin and kaempferol, and the phenolic acids, caftaric and coutaric acid. On a wet weight basis, some PPTs, such as protocatechuic and oxidized cinnamic acids, are present at a higher level in raisins compared to grapes. In human intervention studies, raisins can lower the postprandial insulin response, modulate sugar absorption (glycemic index), affect certain oxidative biomarkers, and promote satiety via leptin and ghrelin. However, only limited numbers of studies have been performed, and it is not clear to what extent the PPT component is responsible for any effects. More research is required to establish the bioavailability and health effects of the PPT component of raisins, the effects of raisins on health biomarkers in vivo in humans, and how these effects compare to grapes and wine.
Metabolism. 2009 Jan;58(1):120-8. doi: 10.1016/j.metabol.2008.08.014. Raisins and walking alter appetite hormones and plasma lipids by modifications in lipoprotein metabolism and up-regulation of the low-density lipoprotein receptor.
Puglisi MJ1, Mutungi G, Brun PJ, McGrane MM, Labonte C, Volek JS, Fernandez ML.
The purpose of this study was to determine the effects of consuming raisins, increasing steps walked, or a combination of these interventions on lipoprotein metabolism and appetite hormones by assessing plasma apolipoprotein concentrations, cholesterol ester transfer protein activity, low-density lipoprotein (LDL) receptor messenger RNA (mRNA) abundance, and plasma ghrelin and leptin concentrations. Thirty-four subjects (17 men and 17 postmenopausal women) were matched for weight and sex and randomly assigned to consume 1 cup raisins per day (RAISIN), increase the amount of steps walked per day (WALK), or a combination of both interventions (RAISIN + WALK). The subjects completed a 2-week run-in period, followed by a 6-week intervention. Ribonucleic acid was extracted from mononuclear cells, and LDL receptor mRNA abundance was quantified by use of reverse transcriptase polymerase chain reaction. Plasma apolipoproteins were measured by Luminex (Austin, TX) technology. Apoproteins A-1, B, C-II, and E and cholesterol ester transfer protein activity were not altered for any of the groups. In contrast, apolipoprotein C-III was significantly decreased by 12.3% only in the WALK group (P < .05). Low-density lipoprotein receptor mRNA abundance was increased for all groups after the intervention (P < .001). There was a significant group effect for plasma leptin (P = .026). Plasma concentrations increased for RAISIN and RAISIN + WALK. Similarly, plasma ghrelin concentrations were elevated postintervention for both groups consuming raisins (P < .05). These data suggest that walking and raisin consumption decrease plasma LDL cholesterol by up-regulating the LDL receptor and that raisin consumption may reduce hunger and affect dietary intake by altering hormones influencing satiety.
J Food Sci. 2013 Jun;78 Suppl 1:A26-9. doi: 10.1111/1750-3841.12152.
Raisins and oral health.
Wong A1, Young DA, Emmanouil DE, Wong LM, Waters AR, Booth MT.
Traditionally, raisins have been thought to promote dental caries due to their suspected "stickiness" and sugar content. Current research identifies some evidence contrary to traditional thought, suggesting that raisins may not contribute to dental caries. This article reviews new findings with regards to raisins and the 3 conditions that are thought to contribute to the formation of dental caries; low oral pH, adherence of food to teeth, and biofilm (bacterial) behavior. The studies reviewed concluded that raisin: consumption alone does not drop oral pH below the threshold that contributes to enamel dissolution, do not remain on the teeth longer than other foods, and contain a variety of antioxidants that inhibit Streptococcus Mutans, bacteria that is a primary cause of dental caries. Further research in this area should be considered.